Airtasker

Being a new startup in Australia we needed a reliable hosting partner that could manage our platform and cope with periods of high traffic to our apps.

Anchor not only provided a stable and scalable service but went above and beyond in terms of consultation and around the clock support. We’re super glad to know that we can always count on Anchor as one of our partners!”

The Company

￼Airtasker is an exciting new startup that connects people who need stuff done with people who can Get Things Done.

With their big public launch imminent, Airtasker needed close support to look after things as hordes of visitors deluged their servers.

60000

people across Australia

1100000

$ worth of jobs created

The challenge

Every startup dreams of big media exposure, and that’s what Airtasker got, though with much less warning than expected.

Anchor got the call less than 24 hours before Airtasker was due to hit the airwaves, with a mention on commercial radio as well as features on Today Tonight and A Current Affair.

Anchor swings into action

Late in the evening we got a heads-up from Michael Cindric, Airtasker’s technical lead. They’d be on radio around 4:45 tomorrow afternoon, and on TV shortly after. He had a good idea of how many thousands of visitors to expect and the site had to hold up; could we help?

You bet we could. Airtasker had a pair of modestly specced virtual machines for the site while it was being developed, a VPS-B for the webserver and a VPS-D for the database backend. Based on projected demand, we bumped them up to a VPS-G with 8gb of RAM, and then started tuning the servers accordingly.

Airtasker is a Rails site, using Apache Passenger to run the app. Passenger’s default config is very conservative, so we opened the throttle and increased its worker pool by a factor of six, allowing it to serve more concurrent requests. As a safeguard against possible memory leaks we also enabled periodic recycling of the worker processes.

With Passenger taken care of, we turned to optimising the database. Postgres loves having plenty of memory, so we let it have everything it could take. To let us keep an eye on performance we enabled slow-query logging. In the event of problems, this would enable us to perform a sort of “query autopsy” on the database. If you’re interested in the kinds of optimisation we do, we’ve published a set of general guidelines and configurable parameters that suit most installations.

This was good so far, but we needed a way of knowing that the site was actually running okay when it got busy. With a couple of sysadmins to spare, we set about adding comprehensive monitoring for the site. Our baseline monitoring only tells us whether the webserver is online, so we configured additional checks that actually hit a specified URL and look for a proper response.

This is a great way to ensure that the application is fully functional and can reach the database. This also gives us additional data about how long it took for the page to be served, which is very useful when assessing site performance for users. The techniques we use for comprehensive site monitoring have also been made available online.

The results

Prior to the arrival of the heavy traffic we did some testing. The results of some ad-hoc analysis suggested that the two most important pages identified by the customer, the front page and task-listing page, were at least twice as fast, which is a solid result. Airtasker’s developers would also do some optimisation of the application code to further speed things up.

As traffic arrived, Anchor’s sysadmins kept an eye on things. The surge came in as expected and while loading times increased with the extra demand on the servers, the site didn’t crumble. This made for a few tense hours as the publicity swept through Australian timezones and then tapered off through the evening.

Following the successful handing of their initial wave of publicity, Airtasker opted to keep their servers in the upgraded configuration and signed up for Anchor’s comprehensive management services.

For Jonathan Lui, Airtasker’s Founder and COO, the benefits of having a team of experts on hand is well worth the modest cost.